首页 > 其他分享 >BBS项目后台管理部分总结

BBS项目后台管理部分总结

时间:2023-01-14 19:55:26浏览次数:43  
标签:总结 obj models request site tag 后台 article BBS

BBS项目后台管理部分总结

一、开设的路由

    # 后台管理接口
    path('backend/', views.backend_func),
    # 后台管理之添加文章接口
    path('add_article/', views.add_article_func),
    # 后台管理之文章上传图片
    path('upload_img/', views.upload_img_func),
    # 后台管理之文章编辑
    path('edit_article/<int:article_pk>/', views.edit_article_func),
    # 后台管理之文章删除
    path('delete_article/', views.delete_article_func),
    # 用户头像修改
    path('set_avatar/', views.set_avatar_func),

二、视图函数部分

@login_required
def backend_func(request):
    site_obj = models.Site.objects.filter(site_name=request.user.username).first()
    # 获取当前站点下所有的文章
    article_queryset = models.Article.objects.filter(site=site_obj)

    page_obj = mypage.Pagination(current_page=request.GET.get('page'), all_count=article_queryset.count())
    page_queryset = article_queryset[page_obj.start:page_obj.end]
    return render(request, 'backend/backend.html', locals())
from bs4 import BeautifulSoup


@login_required
def add_article_func(request):
    site_obj = models.Site.objects.filter(site_name=request.user.username).first()
    if request.method == "POST":
        title = request.POST.get('title')
        content = request.POST.get('content')
        category_id = request.POST.get('category')
        tag_list = request.POST.getlist('tag')
        # 将文章内容交给bs4模块处理
        soup = BeautifulSoup(content, 'lxml')  # 第二个参数是解析器 不同的解析器功能不一样 最好用的是lxml 需要提前下载
        tags = soup.find_all()
        for tag in tags:
            if tag.name == 'script':
                tag.decompose()  # 删除script标签
        article_obj = models.Article.objects.create(
            title=title,
            desc=soup.text[0:150],  # 获取文本然后切割150个字符
            content=str(soup),  # 使用处理之后的内容(不包含script标签)
            site=site_obj,
            category_id=category_id
        )
        # 自己去操作文章和标签的第三张表 无法使用add set remove clear
        # for tag_id in tag_list:  # 当tag_list较多的时候 频繁执行create速度会很慢 >>>:大批量数据插入可以使用orm提供的批量插入 bulk_create
        #     models.Article2Tag.objects.create(article=article_obj, tag_id=tag_id)
        tag_obj_list = []
        for tag_id in tag_list:
            article2tag_obj = models.Article2Tag(article=article_obj, tag_id=tag_id)
            tag_obj_list.append(article2tag_obj)
        models.Article2Tag.objects.bulk_create(tag_obj_list)  # 这里还可以使用列表生成式再次缩减代码
        return redirect('/backend/')
    category_list = models.Category.objects.filter(site=site_obj)
    tag_list = models.Tag.objects.filter(site=site_obj)
    return render(request, 'backend/addArticlePage.html', locals())
from django.conf import settings
import os


@login_required
def upload_img_func(request):
    # 返回的数据格式也是有要求的
    """
    //成功时
    {
            "error" : 0,
            "url" : "http://www.example.com/path/to/file.ext"
    }
    //失败时
    {
            "error" : 1,
            "message" : "错误信息"
    }
    """
    back_dict = {
        "error": 0,
    }
    # 获取编辑器上传的图片数据
    img_obj = request.FILES.get('imgFile')
    # 拼接文章图片所存放的路径
    img_dir_path = os.path.join(settings.BASE_DIR, 'media', 'article')
    if not os.path.exists(img_dir_path):
        os.mkdir(img_dir_path)
    img_file_path = os.path.join(img_dir_path, f'{img_obj.name}')  # 针对文件名 为了防止冲突可以添加唯一标识  比如: 用户名+当前时间+文件名
    with open(img_file_path, 'wb') as f:
        for line in img_obj:
            f.write(line)
    back_dict['url'] = '/media/article/%s' % img_obj.name  # 不能返回后端绝对路径 而应该是暴露的接口路径
    return JsonResponse(back_dict)
@login_required
def edit_article_func(request, article_pk):
    site_obj = models.Site.objects.filter(site_name=request.user.username).first()
    article_obj = models.Article.objects.filter(pk=article_pk).first()
    if request.method == "POST":
        title = request.POST.get('title')
        content = request.POST.get('content')
        category_id = request.POST.get('category')
        tag_list = request.POST.getlist('tag')
        # 将文章内容交给bs4模块处理
        soup = BeautifulSoup(content, 'lxml')  # 第二个参数是解析器 不同的解析器功能不一样 最好用的是lxml 需要提前下载
        tags = soup.find_all()
        for tag in tags:
            if tag.name == 'script':
                tag.decompose()  # 删除script标签
        models.Article.objects.filter(pk=article_pk).update(
            title=title,
            desc=soup.text[0:150],  # 获取文本然后切割150个字符
            content=str(soup),  # 使用处理之后的内容(不包含script标签)
            site=site_obj,
            category_id=category_id
        )
        models.Article2Tag.objects.filter(article_id=article_pk).delete()
        tag_obj_list = []
        for tag_id in tag_list:
            article2tag_obj = models.Article2Tag(article=article_obj, tag_id=tag_id)
            tag_obj_list.append(article2tag_obj)
        models.Article2Tag.objects.bulk_create(tag_obj_list)  # 这里还可以使用列表生成式再次缩减代码
        return redirect('/backend/')
    category_list = models.Category.objects.filter(site=site_obj)
    tag_list = models.Tag.objects.filter(site=site_obj)
    return render(request, 'backend/editArticlePage.html', locals())
@login_required
def delete_article_func(request):
    back_dict = {'code': 10000, 'msg': ''}
    if request.method == "POST":
        article_pk = request.POST.get('article_pk')
        models.Article.objects.filter(pk=article_pk).delete()
        models.Article2Tag.objects.filter(article_id=article_pk).delete()
        back_dict['msg'] = '删除成功 准备跑路!'
        return JsonResponse(back_dict)
@login_required
def set_avatar_func(request):
    new_avatar = request.FILES.get('new_avatar')
    # models.UserInfo.objects.filter(pk=request.user.pk).update(avatar=new_avatar)  # update不会再自动加avatar前缀
    user_obj = models.UserInfo.objects.filter(pk=request.user.pk).first()
    user_obj.avatar = new_avatar
    user_obj.save()  # 保存数据
    return redirect('/backend/')

三、前端页面部分

1.backendBasePage

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://cdn.bootcdn.net/ajax/libs/jquery/3.6.1/jquery.js"></script>
    {% load static %}
    <link rel="stylesheet" href="{% static 'bootstrap-3.4.1-dist/css/bootstrap.min.css' %}">
    <script src="{% static 'bootstrap-3.4.1-dist/js/bootstrap.min.js' %}"></script>
    {% block css %}

    {% endblock %}
</head>
<body>
<!--导航条开始-->
<nav class="navbar navbar-inverse">
    <div class="container-fluid">
        <!-- Brand and toggle get grouped for better mobile display -->
        <div class="navbar-header">
            <button type="button" class="navbar-toggle collapsed" data-toggle="collapse"
                    data-target="#bs-example-navbar-collapse-1" aria-expanded="false">
                <span class="sr-only">Toggle navigation</span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
            </button>
            <a class="navbar-brand" href="#">
                {% block title %}
                    BBS
                {% endblock %}
            </a>
        </div>

        <!-- Collect the nav links, forms, and other content for toggling -->
        <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
            <ul class="nav navbar-nav">
                <li class="active"><a href="#">博客 <span class="sr-only">(current)</span></a></li>
                <li><a href="#">文章</a></li>
            </ul>
            <form class="navbar-form navbar-left">
                <div class="form-group">
                    <input type="text" class="form-control" placeholder="搜索">
                </div>
                <button type="submit" class="btn btn-default">搜索</button>
            </form>
            <ul class="nav navbar-nav navbar-right">

                {% if request.user.is_authenticated %}
                    <li><a href="#">{{ request.user.username }}</a></li>
                    <li style="width: 50px;height: 50px;border-radius: 50%;overflow: hidden;display: block"><img src="/media/{{ request.user.avatar }}/" alt="" style="max-width: 100%"></li>
                    <li class="dropdown">
                        <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true"
                           aria-expanded="false">更多操作 <span class="caret"></span></a>
                        <ul class="dropdown-menu">
                            <li><a href="#" data-toggle="modal" data-target="#myModal">修改密码</a></li>
                            <li><a href="#" data-toggle="modal" data-target="#myavatar">修改头像</a></li>
                            <li><a href="/backend/">后台管理</a></li>
                            <li role="separator" class="divider"></li>
                            <li><a href="/logout/">注销登录</a></li>
                        </ul>
                    </li>
                {% else %}
                    <li><a href="{% url 'register_view' %}">注册</a></li>
                    <li><a href="{% url 'login_view' %}">登录</a></li>
                {% endif %}
            </ul>
        </div><!-- /.navbar-collapse -->
    </div><!-- /.container-fluid -->
</nav>
<!--导航条结束-->
<!--模态框开始-->
<div class="modal fade" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">
    <div class="modal-dialog" role="document">
        <div class="modal-content">
            <div class="modal-header">
                <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span>
                </button>
                <h4 class="modal-title text-center" id="myModalLabel">修改密码</h4>
            </div>
            <div class="modal-body">
                <div class="form-group">
                    <label for="">用户名</label>
                    <input type="text" value="{{ request.user.username }}" disabled class="form-control">
                </div>
                <div class="form-group">
                    <label for="">原密码</label>
                    <input type="text" id="old_pwd" class="form-control">
                </div>
                <div class="form-group">
                    <label for="">新密码</label>
                    <input type="text" id="new_pwd" class="form-control">
                </div>
                <div class="form-group">
                    <label for="">确认密码</label>
                    <input type="text" id="confirm_pwd" class="form-control">
                </div>
            </div>
            <div class="modal-footer">
                <span id="error" style="color: red"></span>
                <button type="button" class="btn btn-default" data-dismiss="modal">取消</button>
                <button type="button" class="btn btn-warning" id="setBtn">修改</button>
            </div>
        </div>
    </div>
</div>

<div class="modal fade" id="myavatar" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">
    <div class="modal-dialog" role="document">
        <div class="modal-content">
            <div class="modal-header">
                <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span>
                </button>
                <h4 class="modal-title text-center" id="myModalLabel">修改头像</h4>
            </div>
            <div class="modal-body">
                <form action="/set_avatar/" method="post" enctype="multipart/form-data">
                    {% csrf_token %}
                   <div class="form-group">
                        <label for="">用户名</label>
                        <input type="text" value="{{ request.user.username }}" disabled class="form-control">
                    </div>
                    <div class="form-group">
                        <label for="">原头像</label>
                        <img src="media/{{ request.user.avatar }}/" alt="" width="120">
                    </div>
                    <div class="form-group">
                    <label for="myfile">新头像
                        <img src="/static/img/default.jpg" alt="" width="120" id="myimg">
                    </label>
                    <input type="file" id="myfile" style="display: none" name="new_avatar">
                </div>
                    <input type="submit" class="btn btn-warning btn-block">
                </form>
            </div>
        </div>
    </div>
</div>
<!--模态框结束-->
<!--内容区域开始-->
<div class="container-fluid">
    <div class="row">
        <div class="col-md-2">
            <div class="panel-group" id="accordion" role="tablist" aria-multiselectable="true">
                <div class="panel panel-default">
                    <div class="panel-heading" role="tab" id="headingOne">
                        <h4 class="panel-title">
                            <a role="button" data-toggle="collapse" data-parent="#accordion" href="#collapseOne"
                               aria-expanded="true" aria-controls="collapseOne">
                                博客后台
                            </a>
                        </h4>
                    </div>
                    <div id="collapseOne" class="panel-collapse collapse in" role="tabpanel"
                         aria-labelledby="headingOne">
                        <div class="panel-body">
                            <p><a href="/add_article/">添加文章</a></p>
                            <p><a href="#">添加分类</a></p>
                            <p><a href="#">添加标签</a></p>
                            <p><a href="#">更多操作</a></p>
                        </div>
                    </div>
                </div>
                <div class="panel panel-default">
                    <div class="panel-heading" role="tab" id="headingTwo">
                        <h4 class="panel-title">
                            <a class="collapsed" role="button" data-toggle="collapse" data-parent="#accordion"
                               href="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo">
                                私密后台
                            </a>
                        </h4>
                    </div>
                    <div id="collapseTwo" class="panel-collapse collapse" role="tabpanel" aria-labelledby="headingTwo">
                        <div class="panel-body">
                            Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad
                            squid.
                            3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt
                            laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin
                            coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes
                            anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings
                            occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't
                            heard
                            of them accusamus labore sustainable VHS.
                        </div>
                    </div>
                </div>
                <div class="panel panel-default">
                    <div class="panel-heading" role="tab" id="headingThree">
                        <h4 class="panel-title">
                            <a class="collapsed" role="button" data-toggle="collapse" data-parent="#accordion"
                               href="#collapseThree" aria-expanded="false" aria-controls="collapseThree">
                                友情链接
                            </a>
                        </h4>
                    </div>
                    <div id="collapseThree" class="panel-collapse collapse" role="tabpanel"
                         aria-labelledby="headingThree">
                        <div class="panel-body">
                            Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad
                            squid.
                            3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt
                            laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin
                            coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes
                            anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings
                            occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't
                            heard
                            of them accusamus labore sustainable VHS.
                        </div>
                    </div>
                </div>
            </div>
        </div>
        {% block content %}
            <div class="col-md-10">
                <div>

                    <!-- Nav tabs -->
                    <ul class="nav nav-tabs" role="tablist">
                        <li role="presentation" class="active"><a href="#home" aria-controls="home" role="tab"
                                                                  data-toggle="tab">文章</a></li>
                        <li role="presentation"><a href="#profile" aria-controls="profile" role="tab"
                                                   data-toggle="tab">随笔</a></li>
                        <li role="presentation"><a href="#messages" aria-controls="messages" role="tab"
                                                   data-toggle="tab">日记</a>
                        </li>
                        <li role="presentation"><a href="#settings" aria-controls="settings" role="tab"
                                                   data-toggle="tab">配置</a>
                        </li>
                        <li role="presentation"><a href="#others" aria-controls="settings" role="tab" data-toggle="tab">其他</a>
                        </li>
                    </ul>

                    <!-- Tab panes -->
                    <div class="tab-content">
                        <div role="tabpanel" class="tab-pane active" id="home">
                            {% block articleConetent %}

                            {% endblock %}
                        </div>
                        <div role="tabpanel" class="tab-pane" id="profile">随笔列表</div>
                        <div role="tabpanel" class="tab-pane" id="messages">日记列表</div>
                        <div role="tabpanel" class="tab-pane" id="settings">配置列表</div>
                        <div role="tabpanel" class="tab-pane" id="others">其他列表</div>
                    </div>

                </div>
            </div>
        {% endblock %}
    </div>
</div>
<!--内容区域结束-->
<script>
    $('#setBtn').click(function () {
        $.ajax({
            url: '/set_pwd/',
            type: 'post',
            data: {
                'old_pwd': $('#old_pwd').val(),
                'new_pwd': $('#new_pwd').val(),
                'confirm_pwd': $('#confirm_pwd').val(),
                'csrfmiddlewaretoken': '{{ csrf_token }}',
            },
            success: function (args) {
                if (args.code === 10000) {
                    window.location.href = args.url
                } else {
                    $('#error').text(args.msg)
                }
            }
        })
    })

    // 1.用户头像的实时展示
        $('#myfile').change(function () {
            // 1.产生一个文件阅读器对象
            let myFileReaderObj = new FileReader();
            // 2.获取用户上传的头像文件
            let fileObj = this.files[0];
            // 3.将文件对象交给阅读器对象读取
            myFileReaderObj.readAsDataURL(fileObj);
            // 等待文件阅读器对象加载完毕之后再修改src
            myFileReaderObj.onload = function () {
                // 4.修改img标签的src属性展示图片
                $('#myimg').attr('src', myFileReaderObj.result)
            }
        })
</script>

{% block js %}

{% endblock %}
</body>
</html>

2.backnd

{% extends 'backend/backendBasePage.html' %}


{% block css %}
    <link rel="stylesheet" href="media/css/{{ site_obj.site_theme }}/">
{% endblock %}

{% block title %}
    {{ site_obj.site_title }}
{% endblock %}


{% block articleConetent %}
    <table class="table table-hover table-striped">
        <thead>
        <tr>
            <th>标题</th>
            <th>时间</th>
            <th>评论数</th>
            <th>点赞数</th>
            <th>点踩数</th>
            <th>操作</th>
            <th>操作</th>
        </tr>
        </thead>
        <tbody>
        {% for article_obj in page_queryset %}
            <tr>
                <td><a href="/{{ site_obj.site_name }}/article/{{ article_obj.pk }}/">{{ article_obj.title }}</a></td>
                <td>{{ article_obj.create_time|date:'Y-m-d H:i:s' }}</td>
                <td>{{ article_obj.comment_num }}</td>
                <td>{{ article_obj.up_num }}</td>
                <td>{{ article_obj.down_num }}</td>
                <td><a href="/edit_article/{{ article_obj.pk }}/">编辑</a></td>
                <td><a href="#" class="delBtn" article_pk="{{ article_obj.pk }}">删除</a></td>
            </tr>
        {% endfor %}
        </tbody>
    </table>
    <div class="pull-right">{{ page_obj.page_html|safe }}</div>
{% endblock %}

{% block js %}
    <script src="https://unpkg.com/sweetalert/dist/sweetalert.min.js"></script>

    <script>
        $('.delBtn').click(function () {
            let currentBtn = $(this);
            swal({
                title: "你确认要删除吗?",
                text: "一旦删除了 后果自负哦 大概率需要提桶跑路!!!",
                icon: "warning",
                buttons: true,
                dangerMode: true,
            })
                .then((willDelete) => {
                    if (willDelete) {
                        // 用户点击OK按钮 发送ajax请求
                        $.ajax({
                            url:'/delete_article/',
                            type:'post',
                            data:{'csrfmiddlewaretoken':'{{ csrf_token }}','article_pk':$(this).attr('article_pk')},
                            success:function (args) {
                               if(args.code===10000){
                                   swal(args.msg, {
                                        icon: "success",
                                    });
                                   // 使用DOM操作 临时刷新页面
                                   currentBtn.parent().parent().remove()
                               }   else{
                                   swal(args.msg);
                               }
                            }
                        })




                    } else {
                        swal("你个怂货 数据都不敢删!");
                    }
                });
        })
    </script>
{% endblock %}

3.addArticlePage

{% extends 'backend/backendBasePage.html' %}


{% block css %}
    <link rel="stylesheet" href="media/css/{{ site_obj.site_theme }}/">
{% endblock %}

{% block title %}
    {{ site_obj.site_title }}
{% endblock %}


{% block articleConetent %}
    <h2 class="text-center">添加文章</h2>
    <form action="" method="post">
        {% csrf_token %}
        <p>文章标题</p>
        <input type="text" name="title" class="form-control">
        <p>文章内容</p>
        <textarea name="content" id="mycontent" cols="30" rows="10" class="form-control"></textarea>
        <p>文章分类</p>
        <p>
            {% for category_obj in category_list %}
                <input type="radio" name="category" value="{{ category_obj.pk }}">{{ category_obj.name }}
            {% endfor %}
        </p>
        <p>文章标签</p>
        <p>
            {% for tag_obj in tag_list %}
                <input type="checkbox" name="tag" value="{{ tag_obj.pk }}">{{ tag_obj.name }}
            {% endfor %}
        </p>
        <input type="submit" class="form-control btn btn-success btn-block" value="发布">
    </form>
{% endblock %}


{% block js %}
    <script charset="utf-8" src="/static/kindeditor/kindeditor-all-min.js"></script>
    <script charset="utf-8" src="/static/kindeditor/lang/zh-CN.js"></script>
    <script>
        KindEditor.ready(function(K) {
                window.editor = K.create('#mycontent',
                    {
                        width : '100%',
                        height: '600px',
                        resizeType:1,
                        uploadJson : '/upload_img/',
                        extraFileUploadParams : {
                            csrfmiddlewaretoken : '{{ csrf_token }}',

                }
                                       }
                    );
        });
    </script>
{% endblock %}

4.editArticlePage

{% extends 'backend/backendBasePage.html' %}


{% block css %}
    <link rel="stylesheet" href="media/css/{{ site_obj.site_theme }}/">
{% endblock %}

{% block title %}
    {{ site_obj.site_title }}
{% endblock %}


{% block articleConetent %}
    <h2 class="text-center">添加文章</h2>
    <form action="" method="post">
        {% csrf_token %}
        <p>文章标题</p>
        <input type="text" name="title" class="form-control" value="{{ article_obj.title }}">
        <p>文章内容</p>
        <textarea name="content" id="mycontent" cols="30" rows="10" class="form-control" >{{ article_obj.content }}</textarea>
        <p>文章分类</p>
        <p>
            {% for category_obj in category_list %}
                {% if article_obj.category == category_obj %}
                        <input type="radio" name="category" value="{{ category_obj.pk }}" checked>{{ category_obj.name }}
                    {% else %}
                        <input type="radio" name="category" value="{{ category_obj.pk }}">{{ category_obj.name }}
                {% endif %}
            {% endfor %}
        </p>
        <p>文章标签</p>
        <p>
            {% for tag_obj in tag_list %}
                {% if tag_obj in article_obj.tags.all %}
                    <input type="checkbox" name="tag" value="{{ tag_obj.pk }}" checked>{{ tag_obj.name }}
                {% else %}
                    <input type="checkbox" name="tag" value="{{ tag_obj.pk }}">{{ tag_obj.name }}
                {% endif %}

            {% endfor %}
        </p>
        <input type="submit" class="form-control btn btn-danger btn-block" value="发布">
    </form>
{% endblock %}


{% block js %}
    <script charset="utf-8" src="/static/kindeditor/kindeditor-all-min.js"></script>
    <script charset="utf-8" src="/static/kindeditor/lang/zh-CN.js"></script>
    <script>
        KindEditor.ready(function(K) {
                window.editor = K.create('#mycontent',
                    {
                        width : '100%',
                        height: '600px',
                        resizeType:1,
                        uploadJson : '/upload_img/',
                        extraFileUploadParams : {
                            csrfmiddlewaretoken : '{{ csrf_token }}',

                }
                                       }
                    );
        });
    </script>
{% endblock %}

标签:总结,obj,models,request,site,tag,后台,article,BBS
From: https://www.cnblogs.com/almira998/p/17052429.html

相关文章

  • BBS项目文章详情页点赞点踩以及评论
    目录BBS项目文章详情页点赞点踩以及评论一、编写思路概览二、编写思路详细1.开设一个全新的路由2.写视图函数3.写文章详情页前端页面4.开设文章点赞点踩以及评论路由5.写点......
  • XXE知识总结
    XML一些基本概念XML被设计用来传输和存储数据。HTML被设计用来显示数据。实体引用在XML中,如果你把字符"<"放在XML元素中,会发生错误,这是因为解析器会把它当作新......
  • order by是怎么工作的?(总结后超简洁版)
    介绍排序的动作可能在内存中完成,内存放不下,则利用磁盘临时文件辅助排序。Mysql有两种排序算法,全字段排序和rowid排序(1)全字段排序简单的说就是把所有要查询的......
  • 一位民办二本学生的年终总结
    前言本人目前就读于天津的一所民本本科院校,现在已经大三,经历不是很丰富,但也有遗憾和收获。年度成就自学之路编程语言:python、结构化梯形图(GXworks2)深度学习框架:ten......
  • 机器学习基本概念总结
    1,余弦相似度与欧氏距离1.1,余弦相似度通过对两个文本分词,TF-IDF算法向量化,利用空间中两个向量的夹角,来判断这两个向量的相似程度:(计算夹角的余弦,取值0-1)当两个向量夹......
  • 2022年,年总总结
    本不想写年终总结的,可是无论过的有多糟,总该记录下这一年里点点时光。这一年,过的跟神经病一样2022年,可以说一整年都被浪费了,人生也挂上倒挡,仿佛跌倒了一样,但是跌倒可以爬......
  • 做题总结
    1.字符串问题无重复字符的最长子串我的做法:dp[i]表示以s[i]结尾的最长无重复字串,更新方程if(i-dp[i-1],i-1)没有和dp[i]重复的元素, dp[i]=dp[i-1]+1elsedp[i]=i-......
  • 细节错误总结
    ElementalDecompress 当输入之后发现明显不可行的时候不要在for里面break会影响下一次的输入D-FriendlySpiders建图一定考虑到边的数量的问题......
  • javase知识点总结:三种程序逻辑结构,输入输出
    顺序结构顺序结构程序就是按语句出现的先后顺序执行的程序结构。计算机按顺序逐条执行语句,当一条语句执行完毕,自动转到下一条语句。分支结构if语句1.语法格式1if(......
  • 经典机器学习算法总结
    一,KNN算法1.1,k值的选取1.2,KNN算法思路二,支持向量机算法2.1,支持向量机简述2.2,SVM基本型2.3,对偶问题求解三,K-means聚类算法3.1,分类与聚类算法3.2,K-mea......